The present invention relates generally to brake boosters, and more particularly to a manifold assembly for pneumatically interconnecting a brake booster to an engine and to an electrically-driven vacuum pump.
Automotive vehicles include those with booster-assisted brakes. The engine intake manifold acts as a vacuum source drawing air from the brake booster which is operatively connected to the master brake cylinder. In one known design, a full-time electrically-driven vacuum pump, the engine intake manifold, and the brake booster are pneumatically attached together in a xe2x80x9cYxe2x80x9d configuration without the use of an interconnecting manifold, wherein the brake booster contains various check valves.
What is needed is a manifold assembly for pneumatically interconnecting a brake booster to an engine and to an electrically-driven vacuum pump.
A first expression of a first embodiment of the invention is for a manifold assembly for pneumatically interconnecting an engine to a brake booster and for pneumatically interconnecting an inlet of an electrically-driven vacuum pump to the brake booster and an outlet of the vacuum pump to the engine. In the first expression, the manifold assembly includes an open-top manifold housing coverable by a manifold cover. The open-top manifold housing includes an engine port, a booster port, an orifice, an engine check valve, and a vacuum-pump check valve. The engine port is pneumatically communicable with the engine, The booster port is separate from the engine port and is pneumatically communicable with the brake booster. The orifice is pneumatically communicable with the inlet of the vacuum pump. The engine check valve allows pneumatic flow from the booster port to the engine port but substantially blocks pneumatic flow from the engine port to the booster port. The vacuum-pump check valve allows pneumatic flow from the outlet of the vacuum pump to the engine port but substantially blocks pneumatic flow from the engine port to the outlet of the vacuum pump.
A second expression of a first embodiment of the invention is for a manifold assembly for pneumatically interconnecting an engine to a brake booster and for pneumatically interconnecting an inlet of an electrically-driven vacuum pump to the brake booster and an outlet of the vacuum pump to the engine. In the second expression, the manifold assembly includes a manifold housing. The manifold housing includes an engine port, a booster port, an orifice, an engine check valve, and a vacuum-pump check valve. The engine port is pneumatically communicable with the engine, The booster port is separate from the engine port and is pneumatically communicable with the brake booster. The orifice is pneumatically communicable with the inlet of the vacuum pump. The engine check valve allows pneumatic flow from the booster port to the engine port but substantially blocks pneumatic flow from the engine port to the booster port. The vacuum-pump check valve allows pneumatic flow from the outlet of the vacuum pump to the engine port but substantially blocks pneumatic flow from the engine port to the outlet of the vacuum pump.
A third expression of a first embodiment of the invention is for a manifold assembly for pneumatically interconnecting an automotive engine to a brake booster and for pneumatically interconnecting an inlet of an automotive-battery-driven vacuum pump to the brake booster and an outlet of the vacuum pump to the engine. In the first expression, the manifold assembly includes a manifold housing. The manifold housing includes an engine port, a booster port, an orifice, an engine check valve, a vacuum-pump check valve, a valve enclosure portion, and a pressure sensor receptacle. The engine port is pneumatically communicable with the engine, The booster port is separate from the engine port and is pneumatically communicable with the brake booster. The orifice is pneumatically communicable with the inlet of the vacuum pump. The engine check valve allows pneumatic flow from the booster port to the engine port but substantially blocks pneumatic flow from the engine port to the booster port. The vacuum-pump check valve allows pneumatic flow from the outlet of the vacuum pump to the engine port but substantially blocks pneumatic flow from the engine port to the outlet of the vacuum pump. The valve enclosure portion is in pneumatic communication with the engine port, contains the engine check valve, and contains the vacuum-pump check valve.
Several benefits and advantages are derived from one or more of the expressions of a first embodiment of the invention. The manifold assembly reduces the number of parts otherwise required resulting in lower material costs, lower manufacturing costs, and higher quality. The manifold assembly frees up space that would otherwise be taken up by extensive plumbing connections. The manifold assembly acts as a noise reduction chamber and also routes the noise of the vacuum pump to the engine as can be appreciated by the artisan. The manifold assembly arrangement for the vacuum-pump check valve allows the vacuum-pump check valve to also act as an elastomeric valve which increases the performance of the vacuum pump by preventing backflow into the pump as can be appreciated by those skilled in the art. The pressure sensor receptacle can hold a differential-pressure-sensing sensor which can be used to activate and deactivate the vacuum pump such as activating the vacuum pump in the event of engine failure.